12 vs 115 million, according to the second paragraph of the article:
> In its letter, Slack warned Microsoft that “Slack is here to stay,” adding, “We’re just getting started.” But the 4 million users it had at the time would increase to just 12 million four years later, while Microsoft — which added Teams to its 365 bundle without increasing the price — took Teams from zero to 115 million users.
idk where they are getting those numbers though. I've had classes, jobs, etc. which all use Slack, I've never used Microsoft Teams even once. Both my undergrad and graduate colleges give me a free 365 subscription though, which means that me and every other college student could have been counted
As a counter-anecdata, I’ve gone three jobs using only Teams - in one case they had explicitly rejected Slack on the basis of price. My daughter also uses Teams for school.
Same anecdata here (EU) - Kids use Teams for distance learning, pretty much every larger company uses teams (and to some extend zoom) due to the Covid situation.
Hardly anyone even knows slack exists. Everyone knows and uses teams.
> In its letter, Slack warned Microsoft that “Slack is here to stay,” adding, “We’re just getting started.” But the 4 million users it had at the time would increase to just 12 million four years later, while Microsoft — which added Teams to its 365 bundle without increasing the price — took Teams from zero to 115 million users.